Halogen incandescent lamps provide about four times as much light output than ordinary miniature incandescent lamps. Flashlights using halogen incandescent lamps, thus, are eminently suitable as emergency light sources, and they can also readily be connected to warning flashers, by incorporating any suitable flashing circuitry with the flash lamps.
Flashlights of the type to which the present invention relates usually have a head portion with a reflector to concentrate light from the light source--in the present case the halogen incandescent lamp--and have a housing body portion to receive primary, or rechargeable batteries. Flashlights with halogen incandescent lamps increasingly penetrate the market. By shifting the head portion of the flashlight, by a sliding connection, with respect to the body portion, it has been possible to change the light distribution derived from the light source itself. The cone angle of light reflected by the reflector thus could be changed. Yet, the sliding connection left the reflector in light-reflective reflective relationship with respect to the light source--in other words, the bulb remained always within the reflector system. While this permits changing the cone angle of the emitted light, or the light distribution on an imaging surface, all-around illumination was not possible.
Emergency or warning light sources heretofore used only miniature incandescent lamps of standard construction. Usually, they provide a yellow warning flashing light, and, alternatively, white continuous light, with a narrow beam. Frequently, two different bulbs were used to, selectively, provide the flashing warning light or the concentrated beam. Use of two bulbs is costly and results in a complex construction of the flashlight-warning light combination. It has been proposed to provide flashlights-warning lights with only a single bulb. In such arrangements, the head of the flashlight usually is made of a yellow plastic material, with a clear transparent cover at the head end. The reflector, in such arrangements, is so placed that, in continuous illumination as well as in flashing illumination, light is always emitted towards all sides. Thus, both the clear transparent cover, as well as the remaining yellow plastic portion of the flashlight is illuminated. If flash lamp use is made of, light is lost due to the illumination of the yellow transparent warning region of the flashlight head; if only warning is to be intended, light is lost because some is transmitted through the transparent end portion, otherwise used for torch, or flashlight use.